a. xylem -- usually a solid central strand in roots
b. phloem -- in bundles just exterior to the xylem

5. Monocot vs. Dicot

III. Root Systems.

A. The pericycle produces additional tissues.

1. single layer of cells that lies just inside the endodermis
2. undifferentiated cells; capable of dividing
3. source of branch roots by primary growth
4. Pericycle may also give rise to secondary growth in roots

a. roots which develop from the shoot system; i.e. in a weird place
b. same as "aerial roots" in your text

IV. Root functions and specializations.

A. Primary functions of the root system

1. anchorage & support
2. absorption of water and minerals
3. storage of photosynthates

B. Specializations of roots

1. suckers
2. pneumatophores
3. contractile roots
4. mycorrhizae

a. association between fungal filaments and plant roots
b. plant gets water and minerals from greater area (like with root hairs)
c. fungus gets nutrients manufactured by the plant
d. four in five plants have mycorrhizae

Plants are divided into two organ systems; what are they? How are they produced?

Plants are composed of three organs; what are they?

Plants have three tissue systems; what are they? How are they produced?

How is development in plants different from development in animals?

What are the three stages in the process of development, and what happens in each?

What are the three basic patterns of xylem maturation? How do they differ? Which is most common in roots? What are the physical and developmental differences between protoxylem and metaxylem?

How does the root cap help to protect the root apical meristem? What other function does it serve?

How is the epidermis of the root different from epidermis of the shoot?

What are root hairs and what is their function? At what stage of development do they appear? How are root hairs like mycorrhizae? How different?

What is the difference between cortex and pith? To which tissue system do they belong? From which primary meristem do they develop? Which plants have a region of pith in their roots?

Where is the endodermis found in the root? What is its function? How does the Casparian strip make this function possible? What is the chemical composition of the strip?

Where is the vascular tissue located in roots? How is it arranged in dicots? in monocots?

What are dicots and monocots?

Where is the pericycle located in the root? What are its two functions? How does it accomplish these functions?

How do tap root systems and fibrous root systems differ? How does this difference come about?

What are branch roots and how do they develop? How is this different from branch shoots?

What are adventitious roots and how are they different from branch roots? What are some examples of plants with adventitious roots?

What are the three primary functions of the root system?

Which root specialization pulls the plant deeper into the ground? Which may regenerate the shoot system? Which brings aditional water and minerals into the root? Which brings oxygen into the root? Which provides nitrogen to the root? Which specializations are associations with other organisms?